Plating Bath Temperature Research Articles

ゲル粒子化した塩化スズめっき液を用いた部分置換めっき法の検討

We investigated plating conditions for a tin displacement plating using spherical gel electrolyte particles. Sodium alginate was used as the gelling agent. A 10×10－3 cm3 sodium alginate solution was dropped using a microsyringe into an aqueous solution containing tin chloride, tartaric acid, and thiourea. Optimal results were obtained with 3 wt% sodium alginate concentration and tin plating bath temperature for spherical gel preparation of less than 60 ℃. The alginate spherical gel particle containing the electrolytes adhered to the copper surface. While changing the plating time, tin film thicknesses were investigated using an X-ray fluorescence instrument. The tin film thickness showed a sigmoid growth curve until 120 min of plating time. The tin film thickness at 120 min was estimated as about 800 nm. The gel electrolyte particles on the tin film surface were rougher than those that adhered from an aqueous plating bath. Results suggest that differences in plating film roughness are attributable to the diffusion rate of tin ions to the electrode surface during displacement plating.

Surface Modification of a Photo-Definable Epoxy Resin with Polydopamine to Improve Adhesion with Electroless Deposited Copper

This paper describes the influence of polydopamine surface modifications on the adhesion strength of electroless deposited copper on roughened epoxy resin substrates. The surfaces are characterized with XPS and ToF-S-SIMS. Next, a thorough investigation of the copper–epoxy interface is performed using SEM. Both the polydopamine modification and the variation of the electroless plating bath temperature lead to new insights into the different contributions of chemical and physical adhesion to the overall adhesion strength.

Preparation and characterisation of electrodeposited Ni-Cr/Al<SUB align="right">2O<SUB align="right">3 nanocomposite coatings from a trivalent chromium-based bath

Ni-Cr/Al2O3 composite coatings were co-deposited on mild steel substrates by co-electrodeposition of Ni-Cr alloys and Al2O3 nanopowders from a trivalent chromium plating bath. Variations of Cr and Al2O3 nanoparticles in nanocomposite coatings as a function of Al2O3 concentration in electrolyte, cathode current density, stirring rate and temperature of plating bath was investigated. It was found that these parameters strongly affect the weight percentage of Cr and Al2O3 nanoparticles in the coatings. Microstructural characterisation of the coatings was performed by x-ray diffraction (XRD), scanning electron microscopy and energy-dispersive x-ray analysis (EDX). The corrosion behaviour of the nanocomposite coatings was evaluated by charting the Tafel curves of the solution of H2SO4 (5%) at room temperature. The results showed that the amount of Al2O3 nanoparticles in the coating increases with increasing Al2O3 concentration in electrolyte. This also enhances the co-deposition of Ni and Cr. It was also found that the presence of Al2O3 nanoparticles leads to an increase in hardness and corrosion resistance of the coatings. The distribution of Al2O3 nano-particles across the coatings was uniform even in those cases which resulted from baths of higher concentrations of Al2O3.

Selective Inkjet Printing of Conductors for Displays and Flexible Printed Electronics

A mask-less and selective printing of conductor patterns is of significant importance for all display applications. Printing on structured surfaces such as microlenses or gratings is a challenge. Typically used processes require thermal curing to achieve the conductivity. This limits the applicability to flexible display applications where low temperature processes are preferred, especially for roll to roll (R2R) scale up. We have used an approach of printing a catalyst containing ink, followed by an electroless plating of copper. This paper details the processes, microstructures and properties of highly conductive and printed copper on patterned flat surfaces as well as structures with micro-optic lens structures. A process has been developed on surfaces with lens structures where the conductor is required to be in the valley between the lenses and between structures with narrow lines and narrow pitch. This is a low temperature process, requiring a plating bath temperature of <;45°C and thus very compatible with flexible substrates and R2R processing.

Effect of Electroless Plating Conditions on Toluene Catalytic Combustion Performance of Palladium-Based Catalyst

Catalytic combustion of volatile organic compounds (VOCs) is a high efficient and low-polluted technique. In this paper, the palladium-based combustion catalysts on cordierite honeycomb ceramics (CHC) substrate without interlayer film — Pd/CHC, were prepared by electroless plating method, and the effect of preparing conditions for the catalysts on the catalytic performance of toluene combustion was mainly studied. The optimal conditions were confirmed as follows: plating bath temperature is 60°C, plating time is 30min, palladium salt concentrationis 0.2g/L, and calcination temperature after plating is 500°C. Finally, the stability test further indicated that the Pd/CHC catalyst prepared by the optimal electroless plating conditions has good catalytic stability.

FCCI barrier performance of electroplated Cr for metallic fuel

Abstract As the fuel-cladding chemical interaction (FCCI) between metallic fuel and cladding material can occur at a relatively low temperature, electroplating of Cr as an FCCI barrier on the inner wall of the cladding was proposed. U–10 wt.%Zr and HT9 disks were used as fuel and cladding material to conduct diffusion couple annealing tests at 740 and 800 °C. Two kinds of Cr layers dependent on the temperature of plating bath were electroplated on the surface of the HT9 disks. The Cr layer of 20 μm in thickness, after being electroplated at a bath temperature of 50 °C and a current density of 35 A/dm2 for 1 h, had some cracks and a small-grained structure. However, the Cr layer plated at a bath temperature of 80 °C and a current density of 56 A/dm2 for 2 h showed a dense structure. Both Cr layers inhibited the interaction between U–10 wt.%Zr and HT9 at a relatively high annealing temperature. U penetrated into the Cr layer plated at a bath temperature of 50 °C due to its penetrable structure. The Cr layer plated at a bath temperature of 80 °C showed a better performance than the Cr layer plated at a bath temperature of 50 °C as a diffusion barrier material with less U penetration.

무전해 니켈 도금법을 이용한 고성능 도전사의 제조

Highly conductive yarn was successfully obtained using electroless nickel plating method with palladium activation. In the presence of palladium seed on surface of fibers as a catalyst, continuos nickel layer produced on surface of fibers by reducing <TEX>$Ni${2+}$</TEX> ion in the electroless plating bath to <TEX>$Ni^0$</TEX>. It was found that the Pd-activation using <TEX>$SnCl_2$</TEX> and <TEX>$PdCl_2$</TEX> to deposit palladium seeds on the surface of fibers plays a key role in the subsequent electroless plating of nickel. It also found that electroless nickel plating on the fibers can induce the nickel-plated <TEX>$ELEX^{(R)}$</TEX> fibers to improve the electrical conductivity of the fibers. The thickness of nickel coating layer on the Pd-activated <TEX>$ELEX^{(R)}$</TEX> fibers and specific conductivity of the fiber were increased through electroless plating time. The temperature of nickel plating bath was very effective to enhance the nickel deposition rate.

Electroless Pd membrane deposition on alumina modified porous Hastelloy substrate with EDTA-free bath

This study demonstrates palladium membranes can be electrolessly plated on aluminum oxide-modified porous Hastelloy with hydrazine using an EDTA-free bath. The plating bath temperature affected the membrane surface morphology, with the palladium grain size increasing with increasing temperature. A 7.5 μm thick membrane plating was obtained at room temperature. Helium leak testing confirmed that the membrane was free of defects. Hydrogen permeation test showed that the membrane had a hydrogen permeation flux of 3.3 × 10 −1 mol m −2 s −1 at a temperature of 823 K and at a pressure difference of 100 kPa. There was no measurable interdiffusion between the membrane film and the porous Hastalloy substrate at 823 K. This room temperature membrane plating method provides several advantages such as very high selectivity, stability, favorable energy efficiency and simplicity.

Electroless plating of Co-Fe on the surface of MWCNTs

Multiwalled carbon nanotubes (MWCNTs) were electroless plated with cobalt-iron (Co-Fe). Palladium-atom centers were formed on the surface of MWCNTs by a pretreatment before the plating. Three main parameters, the molar ratio of C Co 2+:C Fe 2+, the concentration of complexing agent, and the temperature of plating bath, were changed to investigate their effects, whereas the concentrations of metal salts and reducing agent and pH were kept unchanged. A layer of metal deposited neatly with a Co-Fe content above 90% was obtained when the molar ratio of C Co 2+:C Fe 2+ was 9:1, the concentration of complexing agent was 0.32 mol/L, and the temperature of plating bath was 60 °C. Metal granules were obtained, or the content of Co-Fe was much less in the other conditions investigated.

Low-phosporous nickel-coated carbon microcoils: Controlling microstructure through an electroless plating process

Carbon microcoils (CMCs) have been coated with a nickel–phosphorus (Ni–P) film using an electroless plating process, with sodium hypophosphite as a reducing agent in an alkaline bath. CMC composites have potential applications as microwave absorption materials. The morphology, elemental composition and phases in the coating layer of the CMCs and Ni-coated CMCs were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The effects of process parameters such as pH, temperature and coating time of the plating bath on the phosphorus content and deposition rate of the electroless Ni–P coating were studied. The results revealed that a continuous, uniform and low-phosphorous nickel coating was deposited on the surface of the CMCs for 20 min at pH 9.0, plating bath temperature 70 °C. The as-deposited coatings with approximately 4.5 wt.% phosphorus were found to consist of a mix of nano- and microcrystalline phases. The mean particle size of Ni–P nanoparticles on the outer surface of the CMCs was around 11.9 nm. The deposition rate was found to moderately increase with increasing pH, whereas, the phosphorous content of the deposit exhibited a significant decrease. Moreover, the material of the coating underwent a phase transition between an amorphous and a crystalline structure. The thickness of the deposit and the deposition rate may be controlled through careful variation of the coating time and plating bath temperature.

Electroless Nickel Phosphorus Plating on AZ31

One of the major drawbacks to using magnesium parts in automotive applications is poor corrosion resistance, which can be improved with a nickel-boron coating placed on a nickel-phosphorus coating, which, in turn, is placed on a phosphate-permanganate conversion-coating layer produced on the magnesium alloy AZ31. This work reports on the determination of the optimum kinetic parameters for producing a coherent nickel-phosphorus coating using an electroless-procedure phosphate-permanganate conversion-coating layer and for studying the effects of the experimental variables of the electroless plating process on the phosphorus content, surface morphology, and structure of the electroless nickel-phosphorus (EN-P) coatings produced. Measurements of the plating rate as a function of experimental variables such as the compositions of the plating bath constituents, temperature, and pH were implemented using the weight-gain method; the phosphorus content of the EN-P coatings was measured using energy-dispersive spectroscopy (EDS) analysis. The surface morphology of the coating was examined using a scanning electron microscope (SEM); X-ray diffraction (XRD) was used to characterize the structure of each coating. An empirical rate law was determined for EN-P plating on a phosphate-permanganate conversion coating. It is found that the deposition rate of the EN-P coating increases by increasing the deposition temperature, the concentration of free nickel ions, and the concentration of hypophosphite ions in the plating bath. In addition, the deposition rate decreases by increasing both the plating bath pH and the concentration of citric acid in the plating bath.

Electrodeposition and characterization of zinc–nickel–iron alloy from sulfate bath: influence of plating bath temperature

The electrodeposition of ternary zinc–nickel–iron alloy was studied in acidic sulfate bath. The comparison between Zn, Ni, and Fe deposition and Zn–Ni and Zn–Ni–Fe co-deposition revealed that the remarkable inhibition of Ni and Fe deposition takes place due to the presence of Zn2+ in the plating bath. The increase in corrosion resistance of ternary deposits is not only attributed to the formation of γ-Ni2Zn11 phase but also to iron co-deposition and formation of iron phase. It was also found that the bath temperature has a great effect on the surface appearance and the deposit composition. The investigation was carried out using cyclic voltammetry and galvanostatic techniques for electrodeposition, while linear polarization resistance and anodic linear sweeping voltammetry techniques were used for corrosion study. Morphology and chemical composition of the deposits were characterized by means of scanning electron microscopy and atomic absorption spectroscopy.

Influence of process parameters for coating of nickel–phosphorous on carbon fibers

The nickel–phosphorous (Ni–P) coating on carbon fiber was studied, using sodium hypophosphite as a reducing agent in alkaline medium. The effects of process parameters such as time, stabilizer concentrations, pH of the plating bath and plating bath's temperature on the electroless Ni–P coating efficiency were investigated. Structural study using X-ray diffraction (XRD) indicates that nickel deposition rate increases with increasing coating time and temperature. The nickel (Ni) recovery efficiency decreases with an increase of stabilizer concentration. From scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX), it has been confirmed that the coating thickness and nickel content increase with an increase of coating time and temperature. The bath temperature of 25 °C, pH of 9, and stabilizer concentration of 25 g/L is good to get a good and uniform coating of Ni on carbon fiber. Thermal stability was studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). From TGA study it is evident that the nickel coating increases thermal stability of the nickel-coated carbon fiber. I– V (current vs voltage) measurement shows Ni-coated fiber is more conducting in nature.

Effects of process parameters on the synthesis of palladium membranes

In this study, palladium film plating was carried out on porous glass supports using the electroless plating technique. This technique was applied to study the effects of bath temperature and reducing agent concentration on the amount and the structure of palladium plated. Hydrazine concentration was fixed at 10 ml/L in the baths using 1 M hydrazine solution while the temperature was changed between 25 and 50 °C. The total mass gain and Pd/Si ratio (wt/wt%) on the surface were obtained as 7.76 mg/cm 2 and 68.7 in a bath temperature of 35 °C, respectively. With the help of LM microscope analysis, thickness of the membrane prepared at this temperature was determined as 31 μm. In the studies in which the bath temperature was examined as a parameter, the minimum total mass gain was obtained in a plating bath temperature of 43 °C. In the second part of this study, in order to study the concentration effect of hydrazine, hydrazine concentration was increased to 15 and 20 ml/L at a bath temperature of 43 °C. It was shown that as a result of increasing the hydrazine concentration from 10 ml/L to 15 ml/L, total mass gain increased more than twice and a denser plating was obtained. On the contrary to expectations, a result less successful than in the study of 10 ml/L concentration was obtained through increasing hydrazine concentration to 20 ml/L. This study showed that bath temperature of 25 °C was too low to carry out effectively autocatalytic reaction on the activated surface. Plating bath decomposed in plating studies performed at 43 °C and 50 °C. In the studies where hydrazine concentrations were examined as a parameter, it was observed that the stability of the bath could not be maintained in each of the three baths throughout the plating time. The highest decomposition rate was also predicted for the study carried out at a hydrazine concentration of 20 ml/L. Decomposition seen at high temperatures and high hydrazine concentrations was explained as a consequence of insufficient EDTA concentrations in plating baths.

Preparation of Fe–Zn alloy deposits by electroless plating

Fe–Zn binary alloys have been deposited by electroless plating. The films were prepared on a copper substrate in contact with an aluminium strip. The effects of the concentration of ligand, reducing agent, pH value, temperature of plating bath and plating time on the deposition rate, and structure and morphology of the films have been studied. A practical electroless plating solution has been developed.

Electrodeposition of Ni–SiC nano-composite coatings and evaluation of wear and corrosion resistance and electroplating characteristics

Abstract Ni–SiC nano-composite coatings with different contents of SiC nano-particulates were prepared by means of the conventional electrodeposition in a nickel-plating bath containing SiC nano-particulates to be co-deposited. The dependence of SiC nano-particulates amount in the nano-composite coatings was investigated in relation to the SiC concentration in bath, cathode current density, stir rate and temperature of plating bath and it is shown that these parameters strongly affected the volume percentage of SiC nano-particulates. The deposition efficiency with and without SiC nano-particulate in bath was studied. The morphology and phases of the electrodeposited nano-composite were studied. The wear behavior of the nano-composite coatings was evaluated on a ball-on-disk test. The corrosion behavior of the nano-composite coatings was evaluated in the solution of 0.5 M NaCl at room temperature. It was found that the cathodic polarization potential increased with increasing the SiC concentration in the bath. The microhardness and wear and corrosion resistance of the nano-composite coatings also increased with increasing content of the SiC nano-particulate in bath. The SiC distribution in the nano-composite coatings at low concentrations of SiC in bath was uniform across the coatings, but at high concentrations, SiC nano-particulates on the surface were agglomerated.

A study on the influence of process parameters on efficiency and crystallinity of electroless Ni–P deposits

In this work, the effect of process parameters such as stabilizer concentrations and plating bath temperature of the electroless Ni–P on efficiency and crystallinity are investigated. Both the nickel recovery and coating efficiencies are defined, quantified and analyzed by varying the above stated basic input process parameters. The integral breadth, crystallite size, microstrain and the relative proportions of amorphous and crystalline phases present in the coating are obtained using the X-ray diffraction technique and analysed.

Electrochemical studies of zinc–nickel codeposition in sulphate bath

The electrodeposition of Zn–Ni alloys from a sulphate bath was studied under different conditions. The bath had the composition 0.40 M sodium sulphate, 0.01 M sulphuric acid, 0.16 M boric acid, 0.20 M zinc sulphate and 0.20 M nickel sulphate. It is found that the plating bath temperature has a great effect on the cyclic voltammograms, galvanostatic measurements during electrodeposition, and consequently linear polarization resistance for corrosion study and the alloy composition. Under the examined conditions, the electrodeposition of the alloys was of anomalous type. X-ray diffraction measurements revealed that the alloys consisted of the δ-phase (Ni 3Zn 22) or a mixture of the two phases δ and γ (Ni 5Zn 21). The comparison between Ni deposition and Zn–Ni codeposition revealed that the remarkable inhibition of Ni deposition takes place due to the presence of Zn 2+ in the plating bath. The Ni deposition starts at −0.85 V in the bath of Ni deposition only, but the deposition starts at more negative potentials in the codeposition bath although the concentration of Ni 2+ is the same in the both baths.

Anodic Electrodeposition of Cerium Oxide Thin Films: I. Formation of Crystalline Thin Films

Cerium oxide thin films have been produced by anodic electrodeposition with a preferred orientation onto a variety of substrates. The Ce(III) ions are complexed with suitable organic ligands in solution to form stable complexes in basic pH solutions. Ligands with mild complexing power are suitable for the formation of cerium oxide films by anodic electrodeposition. The deposition conditions investigated include deposition modes, substrates, complexing agents, pH, temperature, and current density. X-ray diffraction (XRD) and scanning electron microscopy characterizations of the cerium oxide films show that the texture of the films can be controlled by temperature, pH, and current density. XRD analysis reveals that thin films deposited with crystallite sizes as small as 6 nm are possible with this method. A preferred (111) orientation of polycrystalline is formed when the plating bath temperature is higher than 50°C and the current density lower than XPS results reveal that the cerium oxide films deposited at room temperature are nonstoichiometric. © 2003 The Electrochemical Society. All rights reserved.

Characterization of Pd–GaAs Schottky diodes prepared by the electroless plating technique

In this work, Pd–GaAs Schottky diodes have been fabricated by a novel electroless plating technique. A scanning electron microscope (SEM) and Raman spectra are used to characterize the surface morphology of Pd film and Pd–GaAs interface, respectively. Effects of plating variables including concentrations of PdCl2, N2H4 and bulk plating bath, as well as the plating time, on the Pd surface morphology and current–voltage (I–V) characteristics are investigated. From experimental results, it is revealed that I–V characteristics of Pd–GaAs diodes are strongly influenced by the Pd grain size. The Schottky barrier height is increased with decreasing Pd grain size and particle size distribution by lowering the plating temperature and concentrations of PdCl2, N2H4 and bulk plating bath. Moreover, in the presence of sodium, I–V characteristics of the studied diodes are obviously inferior. Based on these results, the high performance Pd–GaAs Schottky diodes can be obtained by appropriately manipulating the plating conditions.